It can be appreciated that electrical data cables may need to be sealed to a barrier, such as a bulkhead, in order to isolate one side of the barrier from the other. For example the barrier may comprise an enclosure having a noxious or dangerous atmosphere on the inside, or there may be equipment within an enclosure which must be hermetically sealed for safe operation.
Various kinds of barrier connectors have been proposed. Typically barrier connectors are provided with a range of bore sizes, and an operator selects a connector having a bore adequate for the number of cables to be passed through the barrier. Some means must be provided for sealing the passage through the connector, because no matter how tightly fitted, some interstices between the cables will remain. Frequently these interstices may be quite large, especially if the cables are loosely fitted in the connector.
Usually a two-part epoxy sealant is stuffed into the bore of the connector as a potting material to make a seal—such sealant is mixed just prior to stuffing, and cures to a hard substance after about 4 hours. If the sealant is semi-solid it can be difficult to stuff around the cables. On the other hand, if the sealant is liquid it is able to fully enter the interstices, but it can be difficult to keep it and the cables it supports in the desired position. Liquid sealant is, before curing, liquid enough to run rather than remaining in place around the cables.
Other features of a typical connector are an ability for attachment to the barrier, and the ability to accept cable sheaths which protect the cable(s) between the barrier and the equipment to which they are connected in use.
Current designs of barrier connectors have disadvantages which the present invention seeks to address.
In this specification, references to closing the passageway through a connector mean closing said passageway sufficiently to prevent liquid sealant running out through it. A full closure is not always required, but depends on the viscosity of fresh sealant.